Rick Junkin

Thanks! All the sensors indicate ambient correctly. And I confirmed K type CHT washer TCs going to the JPI. And on the ground, the JPI and ship CHTs were pretty close, as I indicated earlier. But I didn't spend any time messing with the ship CHT thermocouple, because it seems to be indicating reasonable values. I'll take a closer look when I change the oil in a couple of weeks. Sent from my iPhone using Tapatalk

Yes, I have a Tanis system installed and have the washer t-couples feeding the JPI installed under the Tanis cylinder heaters that are in the thermocouple wells. I'm trying to resolve the difference between what I'm reading on the ship CHT and the JPI CHT (JPI reads ~100FD cooler in cruise). I have a work-around for now, but would ultimately have everything indicating the same. Or at least close to the same. I'll see what JPI says tomorrow, I can't imagine this is the first time this has come up. Cheers, Rick

Thanks for the advice! The washer t-couples are also recommended in the FAQs on the JPI web site for use with a Tanis engine preheat system. I'll talk to JPI again tomorrow and see if they have any updated guidance from what's on their web page. I obviously have a discrepancy that I'd like to get resolved, and I'll take the appropriate actions to do that. The GOOD news is that the JPI CHT indications are consistent across all six cylinders, which means I can establish a JPI CHT reference temperature by crosschecking with the ship's gauge and watch for deviation from that reference to indicate any problems. I've been using 100FD below the ship's indicated CHT up to this point. I fly in normalize mode, which simplifies that task. Thanks again for the point-outs and recommendations. Cheers, Rick

Tanis calls them washer t-couples, to be used under the Tanis heaters specifically for engine monitors - here's what's on my airplane. http://www.tanisaircraft.com/tas2144-k.html Cheers, Rick

Today i took the cowl off and discovered that I have washer thermocouples installed under the Tanis heating element bayonets that feed the EDM 700. I also confirmed that the ship gauge goes to a bayonet thermocouple on #5, which also has a washer thermocouple installed under it for the JPI. The ship thermocouple has an odd knurled connector on the top of it which allows the lead to be disconnected from the thermocouple, presumably to aid in installation? At any rate, it makes me suspicious of the quality of the ship CHT indication. I did a ground run before I took the cowl off and correlated the recorded JPI data with the ship gauge readings I recorded on video with time stamps, and show the JPI reading 285DF, 8% lower than the 310DF indicated on the ship gauge while on the ground. Assuming this is linear, I should see ~350DF on the JPI #5 when the ship gauge reads 380, but that doesn't match what I've seen before while airborne. I reviewed video and JPI data from a previous flight, and the JPI was showing 255DF when the ship gauge was showing 350DF for #5. In other words, none of the data I have makes sense because its inconsistent at similar temperatures, unless the airflow creates a different divergence profile between the two probes. That doesn't make sense to me either. The JPI CHT temperatures are very consistent across all 6 cylinders, with a spread of about 40FD across all 6. So, more data collection. I'll also talk to JPI to get more info on the washer t-couple performance. If I had to guess, I'd say that Rocketman probably had the same setup on his engine and changed everything out to the Tanis combined heater/t-couple to fix it, but I'm only guessing. I'll most likely do that at overhaul or at the next major engine maintenance, which ever comes first. Or I'll figure out that the ship system is toast and just change out the ship probe. Cheers, Rick

I do have an updated EDM 700 that records data, and I checked the unit programming to confirm that it is set to K-type thermocouples. Since the temps I'm seeing on the 700 are 100DF low as compared to the ship's CHT, I was hoping to find that it was set to J-type with K-type probes installed, but no such luck. It was set to K-type. I'm thinking that the Tannis probes that are installed may not be of the grounded variety, and also observed that before starting the last time I preheated the engine, every other cylinder was reading high/low. So there's a lot more going on here than just an errant probe installation. It could be that the Tannis probes have exceeded their service life and need to be replaced anyway. Fortunately its all secondary data and not safety of flight, and the observed/recorded data is consistent, so I can figure it out over the next couple of sorties and at the upcoming oil change in 4 hours when I'll have the cowl off again. Thanks again for the point-outs, I'll report my discoveries and conclusions. Cheers, Rick

Still no new GAMI baseline, but I flew the airplane round trip from St Louis (KSUS) to Jackson TN (KMKL) a week ago with the Tempest fine wires installed, and the airplane ran great. I had some vibration at 2200RPM that I hadn't seen before with the Champion massives, but it smoothed out at 2300 RPM and I'll be recalibrating myself to run at a higher RPM/lower MAP going forward. I know, there may be some further investigation into where the vibe came from, but I'm happy with everything else (easier start, smoother ground running, etc.). I'm planning to take my wife to Lambert's, Home of Throwed Rolls, in Sikeston MO (KSIK) for lunch tomorrow, so should have opportunity to gather more data. I'll let y'all know what I see. Cheers, Rick

I need to drop the cowling and have a look to see what's what, but in my research I believe I may have uncovered another issue with my particular installation that I need to consider - I have a Tannis engine heating system installed. I'll confirm it when I inspect the engine, but my understanding is that the Tannis system uses the CHT bayonet positions for the Tannis combination cylinder heating/CHT thermocouple installs. They are supposed to be K-types thermocouples, but my airplane is a 1989 and I haven't reviewed the log books to see when the Tannis system and the EDM 700 were installed and what exactly is in the thermocouple wells. I have a sinking feeling that I'm looking at about 1.2 AMUs in CHT thermocouple/cylinder heater probes to get the temps to read right. All things being equal in the mean time, it isn't so hard to add 100 to what the EDM 700 is reporting. My guess is that the ship's single CHT is correct, and I will use it as primary until I get some concrete data to prove otherwise. Thanks for the recommendations! Cheers, Rick

Can anyone tell me how this was resolved? JPI EDM 700 CHTs consistently 100 degrees less than ship CHT gauge? I have the exact same issue with the EDM 700 in my TLS and can't find a way to resolve it short of replacing all of the CHT bayonets and hoping that works. I'm not a fan of "HOPE" (High Output Performance Expectations) as a strategy.... Cheers, Rick

Not yet, weather here in STL has been less than cooperative. I won't be able to get airborne again until February due to business travel. I really don't like letting the airplane sit that long, but my job keeps getting in the way. Cheers, Rick

Sorry, contact information for LASAR is www.lasar.com, parts ordering phone (707) 263-0581. Cheers, Rick

I had great luck with LASAR today with getting replacements for my avionics master switch and my BAT 1/BAT 2 switch. If you have the part numbers they can look them up for you. For aircraft serial numbers 27-0001 through 27-0257: 880052-521 switch, landing light 880052-523 switch, taxi light

Thanks for the insight. The injectors were cleaned about 20 hours ago, and #6 has been running the leanest since I've had the airplane. It isn't terribly gross, but the spread is about 0.8gph between #6 and #5, with #1-4 tucked between them with a 0.3 spread. I will have new data the next time I can get airborne, possibly tomorrow. Cheers, Rick

Thanks for your thoughts, one PP to another. The things we found and corrected last weekend cleared up the surging problem I was having. The fuel injector reference line had become disconnected from the system, so the fuel servo was getting ambient pressure at altitude, rather than pressure feedback from the injection system, and that was causing the surging. I was able to confirm the fix on a flight on New Year's Day. The new Tempest fine-wires are intended to improve performance and get things stabilized for selecting the correct GAMI injectors. From past performance, #1-#4 will be the same, #5 will be a smaller orifice and #6 will be a larger orifice. But I wanted to wait to get the data with the fine wire plugs before talking to the folks at GAMI. I hope to have that within the week. Cheers Rick

I'm not too impressed with the non-OEM battery. It charges up ok, but the battery charger gives indications that it's a bad battery. It seems to work fine, but the form/fit is off as its hard to get on and off of the drill motor. The OEM battery slides on and off easily. But for half the price, those may not be bad concessions. Cheers, Rick

Done! The Tempest fine wires are in, and although I only had time to do a ground run tonight, I believe I can see/hear/feel the difference. But it wasn't quite that simple... I went out to the airport today to fly "one last time" with the massive plugs (Champion RHB37E) to gather a bit more data before the plug swap, but on run-up I observed that #5 was not firing on the right mag. I assumed a fouled plug and was going to try clearing it, but I'm a bit superstitious and decided that it was an omen that I should swap to fine wire plugs today. And since I do my engine warm up and run-up on the ramp/non-movement area outside my hangar before talking to ground, it was a simple matter to taxi the 50 yards to shut down and push her back in. I don't think I mentioned that the temperatures were in the teens in STL today... I'm a new M20M owner (May of this year) and have only seen the lower cowling off the airplane for the annual in August. So as I mentioned before, I wasn't looking forward to trying to do it myself. But thanks to Tony Armour's excellent posts about how to do it, I was successful. And my halogen work lights provided just enough heat to keep my hands functional. After pulling the massives and inspecting the plugs, I'm really eager to see what inflight numbers I get with the new plugs. #6 has been first to peak and #5 has been last to peak on the two times I've attempted a GAMI check, and the plug conditions reflect that. It worries me that #5 lower was wet when I pulled it, but I had a good run-up with the new plugs. And I haven't done a good check on the "old" #5 lower yet to determine the condition of the plug. All of the other plugs look good/as expected. I didn't change the oil today for a number of reasons, but the outcome is that when I change it in 7 hours I will also pull the plugs to take a look at how they are doing. Obviously I'm most interested in #5 and #6, but hopefully will have observed their performance numbers and know what to expect. Thanks to all for the expertise and encouragement. Cheers, Rick

The CH2000 is my "other" airplane, planning to instruct in it when I retire in a few years. Please post more if you hear anything more on this one. Cheers, Rick

I was out to visit Mike and the gang at MH Aviation yesterday, and was discussing panel upgrades with Mike. I have an idea of what I want to do, with Mike's Geronimo panel being my gold standard. Saving up my shekels...

I'm not immediately happy with the battery. Form/fit is a bit off, as it is a very tight fit on the Milwaukee drill motor on my Sidewinder. The OEM battery slides on and off easily. And today I had the battery on the charger and the charger was giving the indication that the battery was bad (alternating green and red LEDs on the charger). The battery indicated fully charged on its self-contained charge indicator, and appeared to have a full charge in operation. I dunno, but I won't be buying another one. Cheers, Rick

You guys just about have me talked into it. Re-cowling my airplane isn't one of my favorite things, which is why I was going to wait until the oil change to swap the plugs, but I'm thinking better of it now. I'm headed out of town on business for a couple of weeks, but if I don't have any immediate personal travel requirements when I get back I'll put the new plugs in then. 7 hours of better performance and fuel savings is probably worth it. And I can probably find someone to give me a hand with the cowling. Cheers, Rick

Success! 1088F is back to nominal operation. I was able to record the massive plugs baseline data with that I was looking for, and will have it to compare with the fine wire plug data once I get them installed. I have about 7 hours left on my oil, so I've opted to wait until the oil change to swap out the plugs. No more surging, everything was well behaved. Thanks for the help. Cheers, and Happy New Year, Rick

Thanks to all for the analysis and recommendations. I wanted to have an idea of what to look for when I went out to the airplane this morning and your inputs got me going in the right direction We identified two smoking guns. The first one was easy and obvious, and most surely will eliminate the surging. The fuel injector reference line fitting had come loose behind the rear baffle plate. Ambient pressure was going to the fuel servo, rather than pressures from the injection system, so it makes sense that I was seeing normal operation on the ground (~445'MSL here in St Louis) but having a problem at altitude once I started to lean at 30/2200. I had my annual about 20 hours ago, so that was probably enough time for the fitting to work its way off from an under-torqued condition. Something to add to my post-annual inspection checklist. The second one was the max RPM limit set screw on the prop governor (You were right, Lance). We discovered that the bushing the set screw goes through is stripped out, allowing the screw to migrate enough that the lock nut was starting to loosen up. It was only a change of 15RPM at full throttle climb out, but it was a change. This one would have been easy to miss because the screw was still safety-wired, and the max RPM was consistently hitting 2575. Right up until it wasn't. Prop control had continuously been positive, including being able to pull the RPM down on takeoff and work the the min/max range on the ground. We squared that away and I'm ready to go. I'm starting the New Year off with an early morning flight tomorrow to confirm today's fixes, collect the GAMI check data with the massives installed (EDM 700 download for temps, time stamped GoPro video of the panel for correlated FF/MP/RPM), and then I'll R&R the plugs with the Tempest fine wires, rinse, and repeat. I'll share the comparative data with anyone who might be interested. Thanks again for the point-outs on what to look for. Cheers, and Happy New Year! Rick

The airplane is an 89 TLS/Bravo, roughly 700 SMOH, 120 STOH with flow balanced cylinders from Lycon. No GAMIs with a spread of 1.2gph with 1, 2, 3, and 4 less than .5gph apart and bracketed by 5 and 6, high and low respectively. Massive plugs, with Tempest fine wires ready to go in. The intent of the last two flights was to baseline the parameters with the massives for direct quantified comparison with the fine wires. As to the prop governor, I'm headed out to the airplane this morning to have a look with my mechanic. It performed fine during the ground runs I did yesterday, but I did correct a 15RPM overspeed at full power on initial climb out immediately after takeoff, so we'll be looking to see if anything has come loose there. Thanks for the point outs! Cheers, Rick

Greetings all, I'm looking for information about engine surging at cruise power while leaning to cruise fuel flow, and resolutions to this issue that others may have discovered. I promised my wife I'd start with this - "Riddle me THIS, Batman..." I've encountered this on my last two flight attempts, after having convinced myself that I induced the anomaly on the first sortie with too rapid throttle/mixture adjustments. Flight conditions for the first sortie were 15,500 MSL at the top of the climb out, 34/2400 and 24.5gph (leaned slightly) set on the climb. After leveling off and reaching cruise speed, I set 30/2200 and began leaning fairly quickly to get to about 16gph, but the engine began surging well before then. It caught me by surprise, so I didn't catch all of the parameters during the fluctuations as I enriched the mixture to stop the surging. I tried leaning again with the same results, this time MP looked to be cycling between 30"and about 20", and I'm guessing that RPM was between 2200 and about 1000, based on sound as I didn't see the numbers. Unfortunately I don't have the instrumentation on board to capture the exact numbers. The surging stopped when I went full rich on the mixture and I left it there for an uneventful RTB. I did a run up post flight, and everything was normal. I convinced myself that I had induced this anomaly due to leaning in the climb (first time I had tried that technique) and percolated the fuel with higher than normal temps (1550TIT, CHTs 370-390), leading to a surge condition. On the second sortie (today), I was very deliberate in my adjustments and encountered the same anomaly. Today's flight conditions were 6,500 MSL at 30"/2200RPM, leaning from a cruise climb fuel flow of 25-26gph (full rich) at 34"/2400RPM. Leveled at 6,500MSL with 30/2200 set, I was leaning at a rate of about one full twist of the mixture control every 5 seconds. Leaning through 18.3gph the engine began to surge. I started enriching the mixture at the bottom of the second surge cycle and the surging stopped, so I then went full rich and I left it there for an uneventful RTB. Again, I did a normal run up check on the ground and everything was normal. I then did a high power run up to replicate the inflight engine parameters of 30"/2200, and leaned all the way through RPM decay with no surging. The peak TIT/CHT during the ground run was 1610/376. I also ran my prop through a complete min/max cycle at 2000RPM to hopefully rule out a prop governor issue, with no anomalies noted. Up to this point I have set cruise power and leaned to find peak TIT usually between 15gph and 14gph, and enriched 100DF. I've never had any surging. With the CND ground run results, I'm at a loss for what to look at. Could it be that one of the controllers is having issues? Or perhaps the mixture controller? It only happens inflight... Thanks for any insight you may have, I'm meeting a Mooney expert mechanic at the airplane tomorrow morning to take a look and will report back with our findings. Cheers, Rick